RANUNCULACEAE

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            1. SYSTEMATIC POSITION:
            Bentham & Hooker
            Division: Phanerogames (Seed Plants)
                 Class: Dicotyledones
                        Sub-class: Polypetalae
                               Series: Thalamiflorae
                                     Order: Ranales
                                             Family: Ranunculaceae
           
            2. MORPHOLOGICAL CHARACTERS:
            Habit – Plants are predominantly herbs or a few are shrubs, annual or perennials, a few are aquatic. Perennation takes place by means of rhizomes or by tuberous roots.
            Stem – Mostly herbaceous, in perennial species rhizome present.
            Leaves – Generally alternate or radical, simple or compound, entire but usually much divided in a palmate manner.
            Inflorescence – Solitary terminal or axillary and cymose, rarely racemose.
            Flower – Bisexual, pentamerous, mostly actinomorphic, acyclic or hemicyclic, hypogynous.
            Calyx – Five, free, caducous or wanting, very often petaloid, imbricate or rarely valvate.
            Corolla – Five or more, imbricate, caducous or wanting, nectarines of various forms usually present at the base, in a few there is no distinction between calyx and corolla.
            Androecium – Stamens indefinite, free, anthers adnate, dehiscence by longitudinal slits, extrose.
            Gynoecium – Carpels many, free, rarely united, ovary unilocular, superior, ovules one to many, placentation marginal.
            Fruit – Aggregate, usually an etaerio of achenes or follicles or simple follicle or capsular and rarely berry.
            Seed – Endosperm oily, embryo small, cotyledon epigeal or hypogeal.
            3. FLORAL FORMULA: ⊕⚥K5, C5, Aα, G1-5 or α
            4. COMPARATIVE SYSTEMATIC POSITION AND AFFINITIES:
            The Ranunculaceae is generally considered as one of the most primitive family of dicotyledones. Bentham & Hooker as well as Hutchinson has placed the family Ranunculaceae in the order Ranales of very early dicotyledones. Engler & Prantl, Rendle and others put the family under the advanced Archichlamydeae. Takhtajan has placed it in the order Ranunculales.
            The floral parts of Ranunculaceae are similar in structure and arrangement to those of Magnoliaceae. On the basis of the structure of stamens and carpels, the Ranunculaceae shows resemblance to the Papaveraceae. The Ranunculaceae and Berberidaceae are also phytochemically related in the possession of the alkaloid ‘berberin’. The family can be linked with Rosaceae on account of the presence of free and numerous stamens and carpels. This family shows a combination of primitive and advanced character. The Ranunculaceae are considered primitive in the presence of predominantly herbaceous habit, bisexual and actinomorphic flower, numerous free and spirally arranged stamens and carpels, follicular fruits, and anatropous ovules. They are advanced in having unisexuality, few and whorled appendages, zygomorphy, connation in the gynoecium and achenial fruits.

            5. ECONOMIC IMPORTANCE:
            1. Aconiyum napuellus, Delphinium ajacis, Ranunculus, Anemone, etc. are commonly cultivated as ornamental plants.
            2. The roots of Aconitum heterophyllum yields an alkaloid ‘aconitina’ used in relieving pain and also for palpitation of heart. The roots of Thalictrum foliosum yield drugs specific for opthalmia and other eye troubles. ‘Pulsatilla’ obtained from Anemone pulsatilla is a good tonic for nerve and menstrual disorder.
            3. Seeds of Nigella sativa are used as spices and condiments.
            4. Some plants are ornamental for their showy beautiful flowers e.g., Delphinium ajacis, Ranunculus spp., Paeonia, Aquilegia, Clematis, etc.

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